About the nsfw part
Sadly, you can't control minors to not seeing nsfw. They usually react with the "this door says only for +18, but I will enter anyway!" kind of mentality. Some friends make a warning like (NSFW) at the start of the title, so the people that doesn't want to see the lewd art can just skip it entirely. Does this fix the problem? Of course not. Because kids will ignore the signs no matter how clear they are.
But yes, I agree that minors seeing nsfw drawings IS a problem. I'm an adult, so I can understand why are you worried about this. I don't think that you should stop doing a type of art you like, but at the same time I can see why you made that decision.
jthrash
I’ve been over 18 for about a decade now, so don’t worry about me. I think the WIP art you’re doing here is good so far, but anatomy-wise you should really make her lower body (hips and thighs) much bigger and wider before moving on to coloring and rendering.
Generally, women’s hips are about as wide as their shoulders (you could exaggerate and make them even wider than her entire upper body, too), while men have wider shoulders compared to their hips and waistlines. Unless the actual character in Honkai Star Rail is actually designed this way, then never mind…
Finasty
Those are already same as the shoulder, you may think that's small, but no, i double checking it the lower body is still same as the shoulder, Honkai Star Rail character design to be like normal character and not thick like others, i have the picture, lemme send you in dms and perhaps, it's also bcoz of my own artstyle